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Progress Report No. 3 Final

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1 Progress Report No. 3 Final
Project Title: Evaluation of Fuel Tank Drop Tests and ASTM Tensile Tests conducted by Southwest Research Institute Date: December 13, Submitted To: Dr. Kennerly H. Digges, MVFRI Mr. R. Rhoads Stephenson Prepared By: Dr. Nabih E. Bedewi

2 OUTLINE Questions to be Answered by Study Review of SwRI Tests
Types of Fuel Tanks Tested Drop Tests Material Coupon Testing Nonlinear Finite Element Simulations Model Development Assumptions

3 OUTLINE (cont.) Simulation of Plymouth Grand Voyager Tank
Model Development Simulation Results and Comparison to SwRI Test Summary of Simulation Results Comparison of Generic Shape Tanks Rectangular Tank Simulation Results and Comparison to SwRI Test Rectangular Tank with a Neck Small Rectangular Tank

4 OUTLINE (cont.) Simulation of Different Coupon Tests
SwRI Simple Tensile Test Hydrostatic Pressure on a Curved Coupon Combined Loading on a Curved Coupon Simulation of Plymouth Tank with Gasoline Properties Drop Test Simulation Side Impact Simulation Conclusions and Proposed Future Research Further Simulation Studies Proposed Testing Program

5 Questions to be Answered
Is there an aging effect on the structural integrity of the plastic fuel tanks? If so, do the geometry of the tank, type of plastic, and pinch off strength have an influence on the structural integrity? Are the tensile tests that were conducted by SwRI adequate to replicate the loads seen in the drop tests to assess the strength of the pinch off? What additional tests, if any, should be carried out to complete the evaluation and make final conclusions?

6 Resources Used SwRI final report was reviewed in detail
Emphasis was placed on test conditions, photographs of undamaged and damaged tanks, description of results and conclusions Biokinetics reports I and II were also reviewed to understand how different test regulations and standards address aging and fuel effects The following SAE papers were also obtained and reviewed in detail:

7 Papers Reviewed Crash-Resistant Fuel Tanks for Helicopters and General Aviation Aircraft, SAE740358, 1974 Development of Plastic Fuel Tanks Using Modified Multi-Layer Blow Molding, SAE , 1990 Development of High Capacity Plastic Fuel Tanks for Trucks, SAE921513, 1992 Comparative Life Cycle Assessment of Plastic and Steel Vehicle Fuel Tanks, SAE982224, 1998

8 Papers Reviewed Simulation Studies of Sloshing in a Fuel Tank, SAE , 2002 Structural and Material Features that Influence Emissions from Thermoplastic Multilayer Fuel Tanks, SAE , 2003 Low Permeation Technologies for Plastic Fuel Tanks, SAE , 2003

9 Review of SwRI Tests The following information is extracted directly from the SwRI test report

10 Typical of some SUV tanks mounted behind the rear axle
Types of Fuel Tanks RECTANGULAR Jeep Grand Cherokee Typical of some SUV tanks mounted behind the rear axle * The Saturn tank tested is also rectangular but smaller and with thinner profile

11 Types of Fuel Tanks RECTANGULAR WITH A NECK Plymouth Grand Voyager
Typical of tanks with a narrow shape mounted inside the frame rail and in front of the rear axle or rear suspension

12 Drop Test Accordance with U.S. DOT 49 CFR , Section E “Drop Test”. The Section E “Drop Test” of the referenced standard states that the fuel tanks shall be filled with a quantity of water having a weight equal to the weight of the maximum fuel load of the tank. The fuel tank is filled then dropped from a 30 ft elevation to assess the durability of the fuel tanks and measure the leak rate. After filling the fuel tank with a quantity of water having a weight equal to the weight of the maximum fuel load and selecting the vulnerable point of impact, the fuel tank was then positioned and strapped to the drop apparatus before being hoisted.

13 SwRI’s Department of Fire Technology’s Test Facility, located in
Drop Test DROP TEST SETUP SwRI’s Department of Fire Technology’s Test Facility, located in San Antonio, Texas

14 Drop Test RECTANGULAR TANK PRE AND POST IMPACT

15 Leakage of Conditioned Plymouth Plastic Fuel Tank After Severe Drop
Drop Test RECTANGULAR TANK WITH A NECK PRE-POST IMPACT Leakage of Conditioned Plymouth Plastic Fuel Tank After Severe Drop

16 Thickest Region at Pinch-Off
Material Testing TENSILE TEST Voyager Cherokee Thickest Region at Pinch-Off Location Typical Tensile Test Specimen Coupon ASTM D , “Standard Test Method for Tensile Properties of Plastics”

17 Typical Tensile Test Setup
Material Testing As these coupons were extracted from the fuel tanks, the pinch-off location in each was perpendicular to the long-axis of the specimen parent material. The overall length of the specimen coupons depended on the location of extraction and ranged from 6 in. to 9 in. in length. The thickness of the specimen coupons varied as well, ranging from 0.2 in. to 0.5 in. For all specimen coupons, the thickest region was at the pinch-off location. Typical Tensile Test Setup

18 Typical Axial Load Per Unit Width Versus Displacement Diagram
Material Testing Typical Axial Load Per Unit Width Versus Displacement Diagram

19 Nonlinear Finite Element Simulations
Model Development and Assumptions

20 Model Development Several finite element models were initially analyzed for different geometry tanks of both plastic and steel composition to understand the behavior and assess the importance of the fluid/structure interaction Some of the tank models existed already in public domain vehicle models developed for NHTSA while others were developed specifically for this study, as outlined later

21 Simulation Background
Tank Models Analyzed Initially Chevy C-2500 Truck Toyota RAV 4 Ford Econoline Ford Taurus

22 Effect of Water Simulation with no Water in the Tank (i.e. mass of water included but not the fluid-structure interaction) Deformation at impact point is accurate, but bulging of tank and stress buildup in non-impact points is not represented

23 Modeling Water in the Tank
A new method based on mesh-free elements (SPH) in LS-DYNA was used to model the fluid-structure interaction in the tank

24 Modeling Water in the Tank
Simulation with water effects Deformation at impact point is accurate as well as bulging of tank and stress buildup in non-impact points

25 Modeling Water in the Tank
Simulation with water effects Deformation at impact point is accurate as well as bulging of tank and stress buildup in non-impact points

26 Model Development This numerical model contains high-end simulation tools which are sophisticated and require specialized expertise to develop and use Development of such a simulation model was challenging because there are no systematic tools available for creating and setting-up the coupling between the conventional finite element and the mesh-free (SPH) model, requiring extra attention and significant amounts of effort and time Several initial simulations were conducted to improve and optimize the robustness, efficiency and accuracy of the model. Some of the parameters that were investigated included: particle density, smoothing length, viscosity coefficient, and material parameters Preliminary simulations were performed to ensure that the fluid (water) is at equilibrium prior to impact, and the final state was used as the initial state for the drop test simulations

27 Model Development Initial simulation results using the material data extracted from the coupon tests performed by SwRI showed significantly more deformation compared with the drop test results. After a literature survey on High Density Poly-Ethylene fuel tank material properties a more accurate material data set was used which gave closer results to the drop tests Since the pinch-off region played an important role in the behavior of the fuel tank, extra attention was given to model this area. To represent the exact cross-section and stiffness properties, five sets of beam elements were used around the tank. This technique is selected also to monitor the forces in this region Tanks were filled with water up to 74% capacity of the total volume

28 Modeling the Pinch-off
To model the pinch-off regions, equivalent beam cross-sections were used with geometry properties extracted from the specimen pictures. Circular beams were modeled all around the tank with mm and mm radii. An average value of 0.4 in (10 mm) is used across the whole tank as the thickness value, where the thickness changes between 0.2 in and 0.5 in.

29 Material Properties of the Model
Material model and properties used for Poly-Ethylene plastic Piecewise Linear Plasticity Constitutive Model Density: 0.95E-9 Tons/mm3 Elastic Modulus: 1200 N/mm2 Poisson’s Ratio: 0.3 Yield Stress: 30 N/mm2 Tangent Modulus: 12 N/mm2 Cowper and Symonds strain rate effects with C=90 and P=4.5 Material model and properties for water Elastic Fluid (using SPH) Density: 0.996E-9 Tons/mm3 Poisson’s Ratio: 0.5 Bulk Modulus: N/mm2

30 Simulation of Plymouth Grand Voyager Tank
Model Development and Comparison with SwRI Drop Test

31 Extraction of Tank Geometry
Digitized Voyager (Caravan) Tank

32 FINITE ELEMENT MODEL OF THE TANK
Grand Voyager Tank FINITE ELEMENT MODEL OF THE TANK The total weight of the tank is 73 kg of which 56 kg is the water weight

33 Grand Voyager Tank COUPLED FINITE ELEMENT AND MESHLESS MODEL
Various views of front side

34 Grand Voyager Tank COUPLED FINITE ELEMENT AND MESHLESS MODEL
Various views of back side

35 DETAILED PINCH-OFF REGION
Grand Voyager Tank DETAILED PINCH-OFF REGION

36 Grand Voyager Tank DETAILED PINCH-OFF REGION
Force measurement direction Force measurement direction Three rows of beam elements parallel to pinch-off joint Two rows of beam elements perpendicular to pinch-off joint

37 Grand Voyager Tank MODEL DETAILS Number of Parts 11
Number of Shell Elements 16,876 Number of Beam Elements 1,717 Number of Nodes 16,572 Number of SPH Particles 124,198 Final Simulation Time 0.1 sec. Number of Processors 4 Computation Time 15 hrs

38 Simulation of Grand Voyager Tank Drop Test
ELEMENT PRESSURE

39 Simulation of Grand Voyager Tank Drop Test
DEFORMATION-SLOSHING

40 Simulation of Grand Voyager Tank Drop Test
DEFORMATION-SLOSHING

41 Simulation of Grand Voyager Tank Drop Test
IMPACT REACTION FORCE ON THE GROUND AT POINT OF IMPACT

42 Simulation of Grand Voyager Tank Drop Test
INTERNAL PRESSURE ON TANK WALL AT SELECTED ELEMENT

43 The next series of slides show the results of the forces as measured by the five sets of beam elements; i.e. the forces observed at the pinch-off region during the impact

44 Beam Element Data of Grand Voyager Tank
Notice red spot (high loads) at the neck area Click mouse on image to repeat PINCH-OFF EVALUATION BEAM SET-I

45 Beam Element Data of Grand Voyager Tank
COMPARISON WITH SwRI DROP TEST: FAILURE OCCURRED IN HIGH LOAD NECK AREA AS PREDICTED BY THE MODEL

46 Beam Element Data of Grand Voyager Tank Region with maximum force

47 Beam Element Data of Grand Voyager Tank
PINCH-OFF EVALUATION BEAM SET-II

48 Beam Element Data of Grand Voyager Tank

49 Beam Element Data of Grand Voyager Tank
PINCH-OFF EVALUATION BEAM SET-III

50 Beam Element Data of Grand Voyager Tank

51 Beam Element Data of Grand Voyager Tank
PINCH-OFF EVALUATION BEAM SET-IV

52 Beam Element Data of Grand Voyager Tank

53 Beam Element Data of Grand Voyager Tank
PINCH-OFF EVALUATION BEAM SET-V

54 Beam Element Data of Grand Voyager Tank

55 Beam Element Data of Grand Voyager Tank
MAXIMUM AXIAL FORCES FOUND AT DIFFERENT BEAM ELEMENTS AT THE PINCH-OFF REGION Peak force in perpendicular direction approx. 3,500 N (780 LB)

56 Summary of Simulation Results Plymouth Grand Voyager Tank
The FE analysis predicted the maximum loads at the same location where the pinch-off region ruptured in the test As expected, the maximum force occurred in the tank neck area since the cross section of the tank is narrower leading to increased water pressure and larger buckling load The maximum force predicted is perpendicular to the pinch off joint and is approximately 780 LB (this is 40% higher than the force that failed the specimens in the tensile tests performed by SwRI) The peak force occurred at about 0.02 sec hence the strain rate effect is important (SwRI tensile test peaked in 1.2 min)

57 Comparison of Generic Shape Tanks

58 Generic Tank Simulations
The purpose of this set of simulations is to investigate the effect of tank geometry on the forces generated at the joint The following three tanks were modeled: Rectangular tank of similar size as the Voyager tank without neck (this represents the class of tanks such as the Jeep Grand Cherokee) Same size as above tank but with a neck section (this represents the class of tanks such as the Plymouth Grand Voyager) Rectangular tank with smaller dimensions than first tank (this represents the class of tanks such as the Saturn) In all cases the thickness of the tank walls and the material properties were kept the same as the Voyager model

59 Generic Tank Model MODEL DETAILS Weight:
Number of Parts 10 Number of Shell Elements 18,049 Number of Beam Elements 1,680 Number of Nodes 18,051 Number of SPH Particles 102,259 Final Simulation Time 0.2 sec. Number of Processors 6 Computation Time 28 hrs Weight: Rectangular baseline tank: 75 kg of which 56 kg is water Rectangular tank with neck: 75 kg of which 56 kg is water Rectangular small tank: 48 kg of which 33 kg is water

60 Rectangular Tank (Baseline)
DEFORMATION-SLOSHING

61 Rectangular Tank (Baseline)
DEFORMATION-SLOSHING

62 Rectangular Tank (Baseline)
PINCH-OFF EVALUATION BEAM SET-I

63 Rectangular Tank (Baseline)
PINCH-OFF EVALUATION BEAM SET-II

64 Rectangular Tank (Baseline)
PINCH-OFF EVALUATION BEAM SET-III

65 Rectangular Tank (Baseline)
Peak tensile (+ve) forces (red contours) occur at or near the impact point PINCH-OFF EVALUATION BEAM SET-IV

66 Rectangular Tank (Baseline)
PINCH-OFF EVALUATION BEAM SET-V

67 Rectangular Tank (Baseline)
FAILURE IN SwRI JEEP CHEROKEE TEST

68 Rectangular Tank with a Neck
DEFORMATION-SLOSHING

69 Rectangular Tank with a Neck
DEFORMATION-SLOSHING

70 Rectangular Tank with a Neck
PINCH-OFF EVALUATION BEAM SET-I

71 Rectangular Tank with a Neck
PINCH-OFF EVALUATION BEAM SET-II

72 Rectangular Tank with a Neck
PINCH-OFF EVALUATION BEAM SET-III

73 Rectangular Tank with a Neck
PINCH-OFF EVALUATION BEAM SET-IV

74 Rectangular Tank with a Neck
PINCH-OFF EVALUATION BEAM SET-V

75 Small Rectangular Tank
DEFORMATION-SLOSHING

76 Small Rectangular Tank
DEFORMATION-SLOSHING

77 Small Rectangular Tank
PINCH-OFF EVALUATION BEAM SET-I

78 Small Rectangular Tank
PINCH-OFF EVALUATION BEAM SET-II

79 Small Rectangular Tank
PINCH-OFF EVALUATION BEAM SET-III

80 Small Rectangular Tank
PINCH-OFF EVALUATION BEAM SET-IV

81 Small Rectangular Tank
PINCH-OFF EVALUATION BEAM SET-V

82 Maximum Force Comparisons
Tank with Neck Baseline Smaller Tank Tank with neck (Grand Voyager type) Baseline rectangular tank (Jeep Cherokee type) Small rectangular tank (Saturn type)

83 Summary of Simulation Results Generic Shape Tanks
The FE analysis predicted the maximum loads near the same location where the pinch-off region ruptured in both the rectangular (Cherokee) and tank with neck (Voyager) tests The addition of a neck section in a rectangular tank, keeping everything else similar, increases the forces in the pinch-off region by 50% Reducing the rectangular tank overall dimensions and mass by 30%, keeping everything else similar, reduces the forces in the pinch-off region by 10%

84 Summary of Simulation Results (cont.) Generic Shape Tanks
Voyager pinch-off contact patch Cherokee pinch-off contact patch The Cherokee pinch-off contact area is 30% of the Voyager pinch-off contact area, therefore for the same amount of force: the stress in the Cherokee joint would be three times higher the strength of the Cherokee joint would be a third of the Voyager’s Since we did not receive the tested tanks from SwRI we cannot make similar conclusions about the Saturn Tank. However, if the contact patch area is somewhere in between the Cherokee and Voyager’s, then from the results of the generic tank simulations, the stress in the Saturn joint would be 20% lower than the Cherokee’s.

85 Simulation of Different Coupon Tests
Model Development and Comparison with SwRI Coupon Tests

86 The next series of slides show results of three simulation cases for different coupon tests that were developed to try and force a failure in the pinch-off area. The first scenario is the SwRI tensile test.

87 Simulation of Coupon Tests
Specimen FE model based on Voyager tank properties used in all three cases

88 Simulation of Coupon Tests
CASE I - SIMPLE TENSILE TEST Click on image to see animation Applied Force Applied Force TOP VIEW

89 Simulation of Coupon Tests
CASE I - SIMPLE TENSILE TEST Click on image to see animation EFFECTIVE STRESS

90 Simulation of Coupon Tests
CASE I - SIMPLE TENSILE TEST Click on image to see animation PLASTIC STRAIN

91 Simulation of Coupon Tests
CASE II - HYDROSTATIC PRESSURE TEST uniform pressure Reaction force

92 Simulation of Coupon Tests
CASE II - HYDROSTATIC PRESSURE TEST Click on image to see animation GEOMETRY EXTRACTION Simulation used to obtain curved geometry of Specimen

93 Simulation of Coupon Tests
CASE II - HYDROSTATIC PRESSURE TEST Click on image to see animation PRESSURE BOUNDARY CONDITION highest stresses and strains not at joint

94 Simulation of Coupon Tests
CASE III – SPECIMEN WRAPPED AROUND PIPE Applied force Applied force Fixed Pipe with frictionless surface

95 Simulation of Coupon Tests
CASE III – SPECIMEN WRAPPED AROUND PIPE Click on image to see animation USING CYLINDER highest stresses and strains not at joint

96 Summary of Simulation Results Coupon Tests
A simple tensile test such as the one performed by SwRI is not representative because in the drop test the pinch-off joint is subjected to a bidirectional force along, and perpendicular to, the joint Applying a hydrostatic force on a curved specimen is more representative of the drop test scenario because the primary loads are generated by the water pressure This is not a simple test to perform and therefore an alternative is to place the specimen on a curved low friction device (pipe) and applying a tensile force at the ends

97 Summary of Simulation Results (cont.) Coupon Tests
The results of the simulations clearly show that the latter provides the same type of load distribution as the hydrostatic case and the stress builds up more at the joint However, all three cases were not able to generate a higher stress at the joint than the parent material. It is not clear at this point that there exists a simple coupon test that can generate the load conditions to fail the pinch-off joints The models have a limitation in that they do not represent any micro-cracks in the joint which would initiate an early failure when tested

98 Simulation of Plymouth Tank with Gasoline Properties

99 Simulations with Gasoline
The purpose of this set of simulations is to investigate the effect of the gasoline properties on the behavior of the tanks as compared to the water properties The following two scenarios were modeled: Plymouth Grand Voyager Tank filled 100% with gasoline and dropped from a height of 30 feet similar to the SwRI drop tests. Same tank and fuel as above except the tank is positioned horizontally and is impacted by a rigid wall traveling at 13.4 m/s (same speed as the impacting tank in a free fall from 30 feet); i.e. gravity is perpendicular to the impact direction.

100 Gasoline Filled Plymouth Tank
Vertical Drop

101 Gasoline Filled Plymouth Tank
Vertical Drop

102 Gasoline Filled Plymouth Tank
Side Impact

103 Gasoline Filled Plymouth Tank
Side Impact

104 Forces Parallel to Joint
Force Comparisons Tank filled with water (74% full) Vertical Drop Tank filled with gasoline (100% full) Side Impact Forces Parallel to Joint

105 Forces Perpendicular to Joint
Force Comparisons Tank filled with water (74% full) Vertical Drop Tank filled with gasoline (100% full) Side Impact Forces Perpendicular to Joint

106 Summary of Simulation Results Gasoline Filled Tanks
The behavior of the tanks when filled with gasoline and dropped from 30 feet or impacted horizontally did not show any difference in the crush behavior or the maximum measured loads (this is perhaps only the case when the tank is filled up to 100% of volume since the effect of gravity on the initial state of the fluid and void does not play a role). The behavior of the tanks when filled with gasoline and dropped from 30 feet did not show any change in terms of the overall tank deformation and the location of the maximum pinch-off area forces when compared to the water filled tanks dropped from 30 feet. However, the force-time history comparison shows an increase for the gasoline tanks in the second peak by about 30% and an increase in the total pulse duration by about 36% (since the crush behavior is the same in both cases then this implies an increase in energy; viz. the area under the force-deflection curve, of 36%).

107 Conclusions and Proposed Future Research

108 Conclusions At impact the dynamics of the water sloshing causes the water to continue to move down, and since it is an incompressible fluid the tank has to expand The FE analysis predicted the maximum loads at the same location where the pinch-off region ruptured in both tests (neck area in the Voyager and lower edge in Cherokee) A tank with a thin stiff neck, such as the Voyager tank, cannot expand in the neck area leading to increased water pressure and therefore large stresses develop at the joints The addition of a neck section in a rectangular tank, keeping everything else similar, increases the forces in the pinch-off region by 50%

109 Conclusions (cont.) The maximum force predicted in the Voyager simulation is perpendicular to the pinch off joint and is approximately 780 LB (this is 40% higher than the force that failed the specimens in the tensile tests performed by SwRI) The Jeep Cherokee carries the most amount of fuel of all tanks tested, yet the pinch-off area has the thinnest cross-section (i.e. higher dynamic loads due to water weight and higher stresses due to smaller cross section area) The stress in the Saturn joint is estimated to be 20% lower than the Cherokee’s. The pinch-off contact area is very important and has a significant effect on the ability of the joint to withstand the impact loads (the size of the Cherokee pinch-off contact area is 30% of the Voyager pinch-off contact area)

110 Conclusions (cont.) In all cases the peak force occurred at about 0.02 sec hence the strain rate effect is important (SwRI tensile test peaked in 1.2 min) A simple tensile test such as the one performed by SwRI is not representative because in the drop test the pinch-off joint is subjected to a bidirectional force along, and perpendicular to, the joint It is not clear at this point that there exists a simple coupon test that can generate the load conditions to fail the pinch-off joints The models have a limitation in that they do not represent any micro-cracks in the joint which would initiate an early failure when tested While a tank filled with water up to 74% volume does represent the general crush behavior of the tank when compared to a tank filled with gasoline up to 100% volume, the maximum forces generated at the pinch-off area could be as much as 10% lower and the total pulse duration as much as 36% less

111 Further Simulation Studies
The following two questions may need to be addressed with further simulation studies: The drop test carried out by SwRI is certainly representative of a vehicle impact condition, however, given that the loads that were generated with a gasoline filled tank are more aggressive than those generated by the water filled tank, should the drop height or the amount of water be modified to reflect these changes for a possible future standard test? Is there some other combination of coupon samples and test configurations that could place the right amount and direction of load on the joint to fail it such that a standard test could exist for testing tank joints?

112 Proposed Testing Program
The simulation study clearly shows that there are unique features in each of the tanks tested that some broad conclusions about tank design and testing could be drawn. While the analysis could explain why certain tank designs have higher loads, and therefore would require thicker tank walls and larger pinch-off contact patch sizes, it did not answer the question as to why the conditioned tanks failed while the new ones did not. It is obvious that exposure to fuel may have some degrading effect on the structural strength of joints. However, the results of the simulations also showed that there are some design considerations which could be addressed to reduce the loads and to strengthen the joints. It is believed from the analysis that the tanks tested were subjected to loads at the borderline of the joint strengths. Therefore, more statistically significant tests should be performed.

113 Proposed Testing Program (cont.)
It is proposed to run a set of drop tests to: (a) provide the necessary validation of the FE models, (b) include sufficient statistical significance to get meaningful results, and (c) understand the contribution of fuel exposure in the pinch off area by testing new tanks that have been exposed to fuel for a period of at least 72 hours. The latter is a requirement in a number of fuel tank compliance tests including ECE and military test procedures. The proposed program would include the following 46 drop tests: Test 1: Custom made clear tank to visualize water slosh and tank bulging effects Tests 2-6: 1998 Saturn Twin Cam 4 Dr New tanks (not exposed to fuel) Tests 7-11: 1998 Saturn Twin Cam 4 Dr New tanks (filled w/ fuel for 72 hrs) Tests 12-16: 1998 Saturn Twin Cam 4 Dr Reconditioned tanks Tests 17-21: 1998 Plymouth Grand Voyager New tanks (not exposed to fuel) Tests 22-26: 1998 Plymouth Grand Voyager New tanks (filled w/ fuel for 72 hrs) Tests 27-31: 1998 Plymouth Grand Voyager Reconditioned tanks Tests 32-36: 1998 Jeep Grand Cherokee New tanks (not exposed to fuel) Tests 37-41: 1998 Jeep Grand Cherokee New tanks (filled w/ fuel for 72 hrs) Tests 42-46: 1998 Jeep Grand Cherokee Reconditioned tanks

114 The End


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